Muffler



May 29, 1962 w. H. POWIIIRS MUFFLER Filed Oct. 4, 1957 INVENTOR. 14 47267 gwefisi 1, up I I aFIVE/Sf 3,036,655 MUFFLER Walter H. Powers,Jackson, Mich, assignor, by mesne assignments, to Walker ManufacturingCompany, Racine, Wis., a corporation of Delaware Filed Oct. 4, 1957,Ser. No. 688,270

Ciaims. (Cl. 181-64) My invention relates to mufflers and, inparticular, to mufllers of the type used to silence the exhaust gases ofautomotive internal combustion engines.

It is an object of my invention to provide a muffler construction forpresent day automobiles which may be produced at a reduced cost ofmanufacture and which will eflectively silence the exhaust gases.

In accordance with my invention, a multi-function chamber is provided ina tri-flow type muffler. This chamber serves to cause reversal of flow,provides a cross over connection, and serves as a spit chamber. It alsoincorporates features for breaking slugs of gases into small streams andfor reducing pulsing of the gases. It also provides a volume in whichsmall spit chambers may be disposed about one of the tubes.

These features are illustrated drawings in which:

FIGURE 1 is a longitudinal cross improved muffler;

FIG. 2 is a section taken along the line 22 of FIG. 1; and

FIG. 3 is a section taken along the line 3-3 of FIG. 1.

The mufller shown in the drawings has a shell construction whichconsists of an inner shell l, a layer of asbestos or the like 3 over theinner shell, and an outer shell 5. The shells are preferably oval inshape as can be seen best in FIGS. 2 and 3. The opposite ends of theinner shell 1 are interlocked in beads 7 with the inlet and outletheaders 9 and 11 respectively. Inlet and outlet bushings 13 and 15respectively are inserted in inturned flanges 17 and 19 respectively onthe inlet and outlet headers 9 and 11. The bushings l3 and 15' haveflared ends 21 on the inside and they are spot welded to the flanges 1'7and 19. An inlet tube 23 is spot welded to the inlet bushing 13 andextends into the mufiier. An outlet tube 25 overlaps the inlet tube 23and extends through the outlet bushing 15 and is spot welded to it.

There are three transverse partitions within the muflier shell 1 whichare designated from left to right by the reference numerals 27, 29, and31. Each of these has flanges formed around its periphery whereby thepartitions can be spot welded to the inner shell 1. The flanges of thepartitions 27 and 29 face the inlet header 9 while the flange of thepartition 31 faces the outlet header 11. The partitions 29 and 31 alongwith the tubes 23 and 25 are formed as a subassembly which is insertedin the muffler shell. After such insertion the partitions 31 and 29 arespot welded in place. This can be done readily through the open ends ofthe shell since their flanges face, respectively, toward the inlet andoutlet ends. After these parts have been inserted, the partition 27 isinserted from the inlet end and it has a slip fit over the tube 23. Whenit is in proper position it is spot welded to the shell 1. After thishas been done, the inlet and outlet headers 9 and 11 are forced over theends of the tubes 23 and 25 and their bushings spot welded to the tubes23 and 25. Either before or after this has been done, the heads 7 can berolled to interlock the headers 9 and 11 with the ends of the shell.

The inlet tube 23, as already indicated, extends with a tight fitthrough a flanged opening 33 in the partition 27. It has embossments 35formed on it which lit in a flanged opening 37 in the partition 29 andprovide means for spot welding the tube 23 to the partition as asubassembly in the accompanying section through the 3,3fi,655 PatentedMay 29, 1962 prior to insertion in the mufller. The inner end of theinlet tube 23 is provided with a series of louvers 39 with in thechamber 41 that is located between the partitions 29 and 31. The openend of the inlet tube 23 is spaced a slight distance toward the inletend from the partition 31 so that gas entering the muffler through theinlet tube will flow out of the end of the tube and transversely in thechamber 41, slugs of gas impinging upon the partition 31 and beingpartially broken up. Gas leaves the chamber 41 through a series offlanged openings 43 that are formed in the partition 29. These havenecks or flanges which extend toward the inlet end, i.e., downstream,the openings preferably being about /2 inch in size and 16 in number.Thus, they provide little resistance to the flow of gas but areeffective in breaking the gas slugs up into smaller streams and thusreducing pulsation.

The gas leaving the chamber 41 enters a cross over chamber 45 which isprovided between the partitions 27 and 29. From this chamber the gas canflow into the inner end of the outlet tube 25 and down the length of theoutlet tube through the bushing 15 to the tail pipe. The outlet tube 25is provided with two series of louvers 4-7 and around them is a splitshell type spit chamber forming construction 51 which provides two spitchambers 53. The space between the partition 31 and the outlet header 11constitutes a large volume spit chamber 54 into which gas cancommunicate through the louvers 55 in the outlet tube. The outlet tube25 is supported in a flanged opening 57 in the partition 29 and also ina flanged opening 59 in the partition 31, being spot welded to boththese partitions at a subassembly prior to insertion in the mufiler asalready indicated.

Low frequency sounds are removed by a resonator chamber 61 which isprovided between the inlet header 9 and the partition 27. A tuning neck63 aligned with openings 43 is mounted in the flanged opening 65 of thepartition 27 and spot welded to it at subassembly and constitutes theonly inlet and outlet to chamber 61.

In order to minimize corrosion and provide for the removal of liquidcondensate within the mufller, the top and bottom sides of each of thepartitions 27, 29, and 31 are provided with A1 inch openings 67 that arelocated as close to the shell 1 as possible. With this arrangement thewater within the muffler can slosh back and forth from one chamber toanother and when it is in the warmest chamber, i.e., the chamber 31, itwill be vaporized and removed by passage out through the outlet tube 25.

It will be noted that the chamber 41 serves to perform severalfunctions. It provides a cross over chamber through which the gasesleaving the tube 23 can flow in order to reach the outlet tube 25. Italso provides a return flow chamber so that gases can reach the crossover chamber 45 and the tuning tube 63. It also serves as a spit chamberto act on gases or sound Waves passing through the louvers 39 in theinlet tube 23. It also provides space to house the pancake spit chamberconstruction 51 around the outlet tube 25. Thus, the present muiilerarrangement provides a simplified, economical construction whichembodies three different size spit chambers, a resonator chamber, a tri-10W pattern, and

. two means for breaking up slugs of gas.

I claim:

1. In a mother construction, a shell providing an elongated chamber, apair of transverse partitions next to each other in said chamber, a pairof gas overlapping conveying tubes in said chamber, one of said tubesextending through both of said partitions, the other of said tubesextending through one of said partitions and terminating in spacedrelationship from the other partition to empty in the space between saidpartitions, said two tubes comprising the only gas conveying tubes inthe space between said partitions, the space between said partitions andthrough partitions constituting a cross over chamber and a return flowchamber and providing the only path for the passage of gas from one tubeto the other, and a substantial number of small but nonrestrictiveoutlet openings in said one of the partitions permitting gas to flowfrom said space to the other of said tubes.

2. The invention set forth in claim 1 including louvers formed in thatportion of one of the tubes within the space between the partitions anda shell means around said louvers in said tube located Within the spacebetween the partitions.

3. The invention set forth in claim 2 including a third partition, and atuning tube supported in the third partition and located in alignmentwith said openings in said partition.

4. In a mufller construction, a shell, inlet and outlet headers closingthe ends of the shell, a pair oftransverse partitions next to each otherin the shell, an inlet tube extending through one of the partitions andterminating short of the other partition and projecting as a cantileverinto the space between said partitions, an outlet tube overlapping theinlet tube and extending through both of the the outlet header, louversformed in that portion of the inlet tube within the space between thetwo partitions, and openings in one of the partitions to provide forflow of the gases from the inlet tube through the space between thepartitions to the outlet tube, the entire cross-section of the shellbetween said partitions comprising a return flow path for gas leavingthe inlet tube.

5. In a mufller, an elongated shell having inlet and outlet ends, inletand outlet headers attached to the shell and closing said ends, saidheaders each having an opening therein, an inlet tube extending in theopening in the inlet header, an outlet tube extending in the opening inthe outlet header, said tubes being transversely spaced from each otherand extending longitudinally of the shell and overlapping each other sothe outlet end of the inlet tube is closer to the outlet header than isthe inlet end of the outlet tube, a first transverse partition in theshell between the outlet header and the outlet end of said inlet tube, asecond transverse partition in the shell atthe inlet end of the outlettube, said tubes overlapping in the space between said partitions andsaid inlet tube. projecting as a cantilever into said space, each ofsaid tubes having openings formed in the side walls thereof in saidspace, a shell in said space around the openings in one of the tubes,said second partition having a multiplicity of downstream flangednonrestrictive openings whereby gas can flow in said space from theinlet tube back toward the inlet header and through said flangedopenings, said space comprising the only path for gas to flow from theinlet to be outlet tube, a third partition in said'shell between saidsecond partition and said inlet header and defining with said inletheader a resonator chamber, a t ing tube supported on said thirdpartition and aligned with said flanged openings and providing the soleinlet and outlet to said resonator chamber, said transverse partitionshaving peripheral flanges spot Welded to said shell, the flanges of thesecond and third partitions facing said inlet header and the flange ofthe first partition facing the outlet header, said-inlet tube extendingthrough an opening in the third partition and being spot welded to aflangedneck in the second partition, said outlet tube being spot weldedto flanged necks in said first and second partitions, the space betweensaid first partition and outlet header comprising a spit chamber, saidoutlet tube having openings in that portion thereof extending throughsaid spit chamber. I

6. In a mufller, an elongated shell having inlet and outlet. ends, inletand outlet headers attached to the shell and closing said ends, saidheaders each having an opening thereiman inlet tube extending in theopening in the inlet header, an outlet tube extending in the opening inthe outlet header, said tubes being transversely spaced from each otherand extending longitudinally of the shell and overlapping each other sothe outlet end of the inlet tube is closer to the outlet header than isthe inlet end of the outlet tube, a first transverse partition in theshell between the outlet header and the outlet end of said inlet tube, asecond transverse partition next to the first partition in the shell atthe inlet end of the outlet tube, said tubes overlapping in the spacebetween said partitions, each of said tubes having openings formed inthe side walls, thereof in said space, a shell in said space around theopenings in one of the tubes, said second partition having amultiplicity of downstream flanged nonrestrictive openings whereby gascan flow in said space from the inlet tube back toward the inlet headerand through said flanged openings, said space comprising the only pathfor gas to flow from the outlet end of the inlet tube to the inlet endof the outlet tube, said transverse partitions having peripheral flangesspot welded to said shell, the flanges of the second partition facingsaid inlet header and the flange of the first partition facing theoutlet header, said inlet tube being spot welded to a flanged neck inthe second partition, said outlet tube being spot welded to flangednecks in said first and second partitions, the space between said firstpartition and outlet header comprising a sound attenuating chamber, andmeans for connecting said chamber to gas flowing through the muffler.

7. In a muffler, an elongated shell having inlet and outlet ends, inletand outlet headers attached to the shell and closing said ends, saidheaders each having an opening therein, an inlet tube extending in theopening in the inlet header, an outlet tube extending in the opening inthe outlet header, said tubes being transversely spaced from each otherand extending longitudinally of the shell, and overlapping each other so.the outlet end of the inlet tube is closer to the outlet header than isthe inlet end of the outlet tube, a first transverse partition in theshell between the outlet header and the outlet end of said inlet tube, asecond transverse partition in the shell at the inlet end of the outlettube and next to the first partition, said tubes overlapping in thespace between said partitions, at least one of said tubes havingopenings formed in the side walls thereof in said space, said secondpartition having a multiplicity of downstream flanged nonrestrictiveopenings whereby gas can flow in said space from the inlet tube' backtoward the inlet header and through said flanged openings, said spacecomprising the only path for gas to flow from the inlet to the outlettube, said transverse partitions having peripheral flanges spot weldedto said shell, the flanges of the second partition facing said inletheader and the flange of the first partition facing the outlet header,said inlet tube being 'spot Welded into a flanged neck in the secondpartition, said outlet tube being spot welded to flanged necks insaidfirst and second partitions. V

8. In a muffler, an elongated shell having inlet and outlest ends, inletand outlet headers attached to the shell and closing siad, ends, saidheaders each having an opening therein, an inlet tube extending in theopening in the inlet header, an outlet tube extending in the opening inthe outlet header, said tubes being transversely spaced from each otherand extending longitudinally of the shell and overlapping each other sothe outlet end of the inlet tube is closer to the outlet header than isthe inlet end of the outlet tube, the path for gas flow from said inlettube toward said outlet tube consisting of the entire crosssection ofsaid shell, and a partition having a' multiplicity of downstream flangednonrestrictive openings in the only igas flowing between the tubes, saidopenings being about /2 inch in diameter and having flanged necksextending downstream, there being about 16 of said openings.

. 9. In a mufller, an elongated shell having inlet and outlet ends,inlet and outlet headers attached to the shell and closing saidends,said headers each havingv an opening therein, an inlet, tube extendingin the opening in the inlet header, an outlet tube extending in theopening in the outlet header, means including a transverse partitionproviding a chamber across the entire cross section of the shell, saidtubes being transversely spaced from each other and extendinglongitudinally of the shell and overlapping each other in siad chamberso the outlet end of the inlet tube is closer to the outlet header thanis the inlet end of the outlet tube, said chamber forming the only pathfor gas leaving the inlet tube to flow to the outlet tube, saidpartition having a multiplicity of flanged nonrestrictive openings inthe path of gas flowing through said chamber from the inlet tube to theoutlet tube, a second partition in said shell located in line with saidflanged openings and defining with one of said headers a resonatorchamber, and a tuning tube supported on said second partition andaligned with said flanged openings and providing the sole inlet andoutlet to said resonator chamber.

10. In a mufller, an elongated shell having inlet and outlet ends, inletand outlet headers attached to the shell and closing said ends, saidheaders each having an opening therein, an inlet tube extending in theopening in the inlet header, an outlet tube extending in the opening inthe outlet header, said tubes being transversely spaced from each otherand extending longitudinally of the shell and overlapping each other sothe outlet end of the inlet tube is closer to the outlet header than isthe inlet end of the outlet tube, a first transverse partition in theshell between the outlet header and the outlet end of said inlet tube, asecond transverse partition in the shell at the inlet end of the outlettube and next to the first partition, said tubes overlapping in thespace between said partitions,

said second partition having a multiplicity of downstream flangednonrestrictive openings whereby gas can flow in said space from theinlet tube back toward the inlet header and through said flangedopenings, a third partition in said shell between said second partitionand said inlet header and defining with said inlet header a resonatorchamber, a tuning tube supported on said third partition and providingthe sole inlet and outlet to said resonator chamber, said transversepartitions having peripheral flanges spot welded to said shell, theflanges of the second and third partitions facing said inlet header andthe flange of the first partition facing the outlet header, said inlettube extending through an opening in the third partition and being spotwelded to a flanged neck in the second partition, said outlet tube beingspot welded to flanged necks in said first and second partitions, thespace between said first partition and outlet header comprising a spitchamber, said outlet tube having openings in that portion thereofextending through said spit chamber.

References tilted in the file of this patent UNITED STATES PATENTS1,541,275 Powell June 9, 1925 2,193,791 Hollerith et a1. Mar. 19, 19402,337,300 Noblitt Dec. 21, 1943 2,618,354 Hedrick Nov. 18, 19522,652,128 Cary Sept. 15, 1953 2,800,973 Cary et al July 30, 19572,899,007 Morrish et al Aug. 11, 1959

